Telefonaktiebolaget Lm Ericsson (publ)

Cellavision Ab

Gambro Ab

Gambro Lundia Ab

Optis Cellular Technology, LLC

Anders Rosenqvist

Bengt Lindoff

Andres Reial

Niklas Andgart

Johan Nilsson

Erik Linderup

Douglas Allan Cairns

Andreas Cedergren

Martin Almers

Bj&ouml;rn Ericson

Magnus Pettersson

Muhammad Ali Kazmi

Stephen J Grant

Gregory Edward Bottomley

Lars Sundström

Christian Bergljung

Elias Jonsson

Ari Kangas

Fredrik Nordström

Bo Lincoln

Bo Magnus Bernhardsson

Matthias Kamuf

Fredrik Tillman

Thomas Olsson

Christer F&aring;hraeus

Daniel Elvin

Anders Heyden

Per Sennmalm

Lars SUNDSTRÖM

A method is disclosed for processing a received signal in the presence of an interference of a first type within the bandwidth of a desired signal of the received signal. The method comprises filtering the received signal using at least a first filter having at least a first filter characteristic to produce a filtered signal wherein the interference of the first type is suppressed. Furthermore, the method comprises determining a desired data stream from the filtered signal, basing the determination at least on the first filter characteristic. A method is also disclosed for processing a signal where the method comprises receiving an indication of whether interference of a first type is present in a frequency interval within the bandwidth of the signal, filtering the signal using at least a first filter having at least a first filter characteristic to produce a filtered signal wherein the filtered signal is suppressed in the frequency interval; and transmitting the filtered signal. Corresponding devices, systems and computer program products are also disclosed.

Methods, devices and systems for processing a signal in the presence of narrowband interference

Methods and apparatus for changing the transmission/reception setup of a base station (BS) in a communication network to another transmission/reception setup (such as one using fewer transmit antennas and/or lower channel bandwidths) without affecting communication with user equipments involve 'replacing' the existing BS with a 'virtual' BS that has the other transmission/reception setup. Replacement can be performed by, for example, ramping down the power of the existing, or first, BS, which has a respective first cell identification (ID), and simultaneously ramping up the power of the virtual, or second, BS, which has a respective second cell ID.

Energy-efficient network methods and apparatus

Methods, a user equipment and a radio network node relating to estimation of a channel quality indicator, CQI, are provided. A first reference signal is carried by a downlink channel of a radio communication system. The user equipment receives from the radio network node information about scheduling of a downlink transmission to the user equipment and information about a second reference signal being different from the first reference signal. Furthermore, the user equipment receives from the radio network node the downlink transmission. The downlink transmission comprises the first reference signal and the second reference signal. Next, the user equipment estimates the CQI based on the first reference signal and the second reference signal.

Estimation of channel quality indicator using additional reference signals

A method is disclosed of scheduling up-link transmissions for a number of terminals of a wireless communication system into a number of groups, wherein each group comprises terminals intended for simultaneous up-link transmission during a respective period of time. A subset metric may be calculated for each of a number of subsets of terminals based on transmissions received from the terminals of the subset. The subset metric is indicative of a simultaneous transmission suitability measure for the terminals of the subset. The subsets may be processed in subset metric order, starting with the subset having a subset metric indicating a least suitability of simultaneous transmission. During the processing, each terminal of the subset that is not already scheduled in a group may be scheduled in a group that does not already comprise another terminal of the subset. Information indicative of the period of time during which a scheduled terminal is intended to transmit may be transmitted to each of the scheduled terminals. Corresponding computer program product, scheduler and arrangement are also disclosed.

Scheduling of up-link transmissions of a wireless communication system

In one embodiment, a method of scheduling transmissions for a base station in a multi-carrier wireless communication network comprises scheduling initial transmissions of data packets for one or more users on a first carrier, without reserving scheduling capacity on the first carrier for retransmissions. Doing so increases the scheduled capacity of the first carrier for initial transmissions. The method further includes scheduling retransmissions, as needed, for given ones of the data packets on one or more second carriers. The method allows more traffic to be scheduled on the first carrier, meaning that multi-carrier transmissions are less frequently needed to convey all of the traffic targeted to one or more receivers. Those receivers therefore spend more time operating with a reduced receiver bandwidth (as compared to the bandwidth required for receiving more than one carrier), which reduces operating power.

Method and apparatus for retransmission scheduling and control in multi-carrier wireless communication networks

A method of delay spread compensation, suitable for use in a communication device a having plurality of receiver antennas, is disclosed. The method comprises receiving a plurality of signals, each via a respective antenna, wherein each signal comprises a signal component corresponding to a transmitted signal, and wherein each received signal experiences a respective channel impulse response having a corresponding delay spread; determining estimates of each of the channel impulse responses; calculating post-coding characteristics based on the estimates of the channel impulse responses; and post-coding the plurality of received signals using the post-coding characteristics to produce at least a first delay spread compensated signal. Corresponding computer program product, processing arrangement and communication device are also disclosed.

Method and arrangement of delay spread compensation

A method of detecting a desired signal within a composite signal provides for suppression of interfering signal(s). The method, implemented in a wireless communication apparatus, for example, includes receiving the composite signal and obtaining sample values therefrom. At least some of the sample values include desired and interfering signal components. The method further includes generating an interfering signal channel estimate by: forming sample pairs for some or all of the sample values; identifying sample pairs of interest as those sample pairs in which the interfering signal component is the same; and calculating the interfering signal channel estimate as an average value determined from one or more of the sample pairs of interest. The method further includes detecting desired signal symbols from the composite signal in a joint detection process that functionally depends on the interfering signal channel estimate.

Method and apparatus for interference suppression using a reduced-complexity joint detection

Allocation of cell IDs in a cellular communication system includes determining a candidate allocation pattern of primary and secondary synchronization signal sequences for a candidate set of two or more cells. A performance metric is applied to the candidate allocation pattern to ascertain a performance indicator for the candidate allocation pattern, wherein the performance indicator indicates a quality of positioning performance for the candidate set of two or more cells. Cell-specific positioning performance for each cell in the candidate set of cells can be considered to derive the performance indicator of the candidate allocation pattern. If the performance indicator indicates acceptable positioning performance, primary and secondary synchronization signal sequences are allocated to respective ones of base stations corresponding to the two or more cells in accordance with the candidate allocation pattern. Otherwise, the process is repeated for a different candidate allocation pattern.

Allocation of primary and secondary synchronization code sequences to cells in a wireless communication system

A signal-to-interference estimate is generated using unknown data symbols in place of or in addition to pilot symbols. Data received over a data channel (traffic channel or control channel) are collected. The data symbols are then used to compute an observation metric based on deviations of the data symbols from a predetermined set of possible data symbols, wherein one of the data symbols and symbol constellation is normalized. A data channel signal-to-interference ratio is then computed based on the observation metric.

Data-aided SIR estimation

Own communication equipment locates a source of wireless transmissions, the own equipment including a serving base station (BS). The serving BS receives, from remote sensors including at least one user equipment (UE), sensing information from which transmitter location information ('location information') can be determined. The location information is oriented in a serving BS coordinate system. The location information can comprise white space sensing information from which a direction of a transmitter relative to a position of the UE can be determined, and pilot signal sensing information from which respective directions of one or more BSs relative to the position of the UE can be determined. The BS transforms the white space and pilot signal sensing information into the location information. Geographical safety margins are determined from the location information, and BS transmissions are adjusted to limit transmitting signals beyond the geographical safety margin area.

Locating a source of wireless transmissions from a licensed user of a licensed spectral resource

Methods and apparatus in a receiver for estimating a received power of at least one signal having a pattern known to the receiver, the signal having being transmitted by at least one antenna. A method includes using a first method of measuring the received power based on the pattern, the first method generating a first sequence of first power estimates; determining whether a predetermined first event has occurred; and if the first event has occurred, changing to a second method of measuring the received power, the second method being different from the first method and generating a second sequence of second power estimates.

Signal power measurement methods and apparatus

A method and apparatus for reducing the computational load associated with computing weighting factors for wireless signals received at a wireless receiver is disclosed herein. The method and apparatus reuses a covariance factor matrix to compute multiple sets of weighting factors for multiple received signals. Particular embodiments factor a covariance matrix determined for a first received signal to determine a covariance factor matrix, and use the covariance factor matrix to determine a set of weighting factors for the first received signal as well as to determine additional sets of weighting factors for one or more additional received signals. The different received signals may be associated with different times, different channelization codes, and/or different frequencies. The weighting factors may be used to weight and combine received signals in a GRAKE receiver or chip equalizer. The weighting factors may also be used to determine a signal quality metric.

Covariance factor matrix reuse

Mobile communication system equipment avoids interfering with another transmitter's operation. Sensing information indicating whether the other transmitter's signal has been detected is received from remote sensors, wherein each of the remote sensors is situated at a respective one of two or more sensor locations. The sensing information and information about the sensor locations is used to ascertain one or more exclusion boundaries needed to avoid interfering with the other transmitter's use of the spectral resource. Beamforming parameters are ascertained that will enable the main node to transmit within one or more predefined geographical areas except for any portion of a predefined area located on a far side of the one or more exclusion boundaries. Two or more adjusted signals are produced as a function of the beamforming parameters and one or more signals to be transmitted. The adjusted signals are transmitted from respective ones of two or more antennas.

Interference avoidance in white space communication systems

An SIR estimate of a communication signal in a wireless communication system receiver is calculated based on soft bit values output by a nonlinear detector. The average amplitude of the detector output soft bits is estimated. The average power of the detector output soft bits is estimated, e.g., as a mean-square or variance. An SIR of the communication signal is estimated based on the soft bit amplitude and power estimates. In particular, the SIR is estimated as the ratio of the square of soft bit amplitude to the difference between the mean square soft bit power and the square of soft bit amplitude, or the ratio of the square of soft bit amplitude to the variance. In either case, the SIR estimate may be scaled to obtain the desired units. The communication signal may be a received signal, or a simulated signal generated using channel estimates obtained from, e.g., a pilot channel.

Blind SIR estimation using soft bit values

In a wireless receiver, an estimated decision boundary for use in detecting symbol values from one group of combined received symbols is calculated based on a estimated traffic-to-pilot channel scaling ratio or an estimated decision boundary corresponding to another group of combined received symbols. By properly combining the information derived from the latter group of combined received symbols with channel estimation information for the former group, a decision boundary estimate for the former group can be obtained without the use of amplitude or power information for the latter group of symbols.

Growing community of inventors

Lund, Sweden

Anders Rosenqvist